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Publication numberUS3499069 A
Publication typeGrant
Publication dateMar 3, 1970
Filing dateAug 18, 1966
Priority dateAug 18, 1966
Publication numberUS 3499069 A, US 3499069A, US-A-3499069, US3499069 A, US3499069A
InventorsSeigle Herald Denton
Original AssigneeStruthers Scient & Intern Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method of making bricks
US 3499069 A
Abstract  available in
Images(5)
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Claims  available in
Description  (OCR text may contain errors)

March 3, 1970 H. D. SEIGLE METHOD OF MAKING BRICKS Filed Aug. 18, 1966 5 Sheets-Sheet 1 MIXER FORMING 24v PRESS FIG. I

INVENTOR:

HERALD D. SEIGLE FIG. 2

March 3, 1970 H. D. SEIGLE 3,

METHOD OF MAKING BRICKS Filed. Aug. 18, 1966 5 Sheets-Sheet 2 B I/IIIIIIIIII/ FIG.4

72 F as q FORMlNG f PRESS :13 14 PRESS I49 H65 INVENTOR. HERALD D. SE IG LE March 3, 1970 H,YD. SEIGLE 3,499,069

METHOD OF MAKING BRICKS Filed Aug. 18, 1966 5 Sheets-Sheet 3 8 I INVENTOR:

HERALD D. SEIGLE March 3, 1970 H. D. SEIGLE 3, 99,

METHOD OF MAKING BRICKS Filed Aug. 18, 1966 5 Sheets-Sheet 4.

FIG. IO

INVENTORZ HERALD D. SEIGLE March 3, 1970 H. SEIGLE 3, 9

} METHOD 0]? MAKING BRICKS Filed Aug.- 18, 1966 5 Sheets-Sheet 5 FIG. II

l3ln '23 gl |3 4-\ FIG. l2

INVENTOR:

HERALD D. SEIGLE Fa. l3

United States Patent 3,499,069 METHOD OF MAKING BRICKS Herald Denton Seigle, Riverdale, N.Y., assignor to Struthers Scientific and International Corporation, a corporation of Delaware Filed Aug. 18, 1966, Ser. No. 573,323 Int. Cl. 1828b 3/02, 13/02, 15/00 US. Cl. 26471 1 Claim ABSTRACT OF THE DISCLOSURE In the process of making brick, graded sand with a moisture content of between 3 and percent and lime are fed to elevated storage hoppers from which these materials pass into a lower weighing hopper to cumulatively weigh a charge of sand and lime which is mixed in a mixer disposed therebelow, passing the mixed charge into an open bottom bin, moving a charging box below the bin and over apertures in a forming press bed to charge the forming press, exerting a forming pressure in the press of at least 1500 pounds per square inch while pounding a platen of the press with an air hammer for at least two seconds, removing formed brick from the press; stacking the formed brick on rail cars, autoclaving the stacked brick on the rail cars with steam for at least seven hours at a temperature of over 390 F., at a pressure of over 225 pounds per square inch, and passing the stacked brick on rail cars through an unloading station with progressively aranged unloading positions and unloading a longitudinal portion of the rail cars at each unloading position.

This invention relates in general to brick manufacturing and, more particularly, to a complete and substantially fully automatic brick or structural block manufacturing facility.

Techniques for making bricks have been known for thousands of years. In recent years many individual steps in the process of brick making and apparatus for handling the materials have been developed and improved. This invention further refines some of the steps and the apparatus for making sand-lime brick. Further, this invention fully integrates the entire sand-lime brick process from start to finish to provide a brick plant which may be substantially fully automatic to produce uniformly superior brick or other structural blocks.

A main object of this invention is to provide a sand- 1ir ne brick or building block plant which more accurately meters the materials and controls the process to provide uniformly superior bricks or building blocks.

Another object of this invention is to provide a superior configuration for bricks to be autoclaved.

A further object of this invention is to provide a superior manual unloading facility for packaging finished bricks.

An additional object of this invention is to provide a superior brick transport means to move brick from forming presses in and out of autoclave units to a packaging area.

Still another object of this invention is to provide a more interrelated and better organized and thus more efiicieut sand-lime brick making facility.

"ice

Many other objects, advantages, and features of invention reside in the particular construction, combination, arrangement of the apparatus or the elements of this in vention and their use in the brick making process as will be understood from the following description and accompanying drawing wherein:

FIGURE 1 is a schematic representation of the process of making sand-lime brick;

FIGURE 2 is a longitudinal section through a sand 1 delivery tunnel with sand piled thereon and with a conveyor carrying sand to a storage hopper;

FIGURE 3 is a perspective view of a broken away central portion of a brick factory building with four storage hoppers thereon with air slide and conveyor loading devices leading thereto;

FIGURE 4 is an elevational view of fragments of the four storage hoppers of FIGURE 3, a weighing hopper, a traveling hopper, two mixers one of which is shown partly in section, and two forming presses;

FIGURE 5 is a side view of elements of a forming press, devices to charge the press, and removal means for formed bricks;

FIGURE 6 is a longitudinal vertical section through a brick which may be made by the process and apparatus of this invention;

FIGURE 7 is a plan view of fragments of the main floor of a brick factory according to this invention;

FIGURE 8 is a side view of rail cars being loaded with formed bricks, the view being taken on line 8-8 of FIGURE 7;

FIGURE 9 is a transverse vertical section through an autoclave unit containing a rail car stacked with formed brick stacked according to this invention to be autoclaved;

FIGURE 10 is a side view of the rail car of FIGURE 9 showing brick stacked thereon according to this invention;

FIGURE 11 is a top view of a three position rail car unloading station;

FIGURE 12 is a view of a rail car unloading position taken on line 12-12 of FIGURE 11; and

FIGURE 13 is a perspective view of brick as packaged in the unloading station of this invention.

Referring to the drawing in detail, FIGURE 1 shows the general method of making brick or building blocks according to this invention. Sand lime, and silica flour are discharged in almost exact predetermined proportions by weight from the hoppers 20, 21, and 22 into a mixer 23. Silica flour is not always required if the sand used has a high enough silica content. The sand should have a moisture content of from 3 to 10 percent and be very carefully graded. This sand must be screened and washed to remove dirt, clay, and water soluble salts. While concrete may be made with over 5 percent mud and salt content in the sand, the sand for the process of this invention cannot contain more than 2 percent mud and salt impurities. Thus, the sand used must be passed through a hydraulic separator and a cyclone separator to remove such impurities as Well as particles finer than mesh.

After this sand, lime, and, in most cases, silica flour is thoroughly mixed in exact proportions in mixer 23, this mixture is passed into a forming press 24 where it is formed and compacted into bricks or other structural shapes. These formed bricks are then stacked in an autoclave for a given time at a given temperature and pressure range to be removed as the product bricks 26. Conventional sand-lime bricks usually withstand up to 4,500 pounds per square inch in compression. The bricks 26 of this invention resist over 7,500 pounds per square inch in compression. This greater strength results from the more exact and greater control of the process and other novel aspects of the apparatus which are hereinafter described.

Referring now to FIGURE 2, washed sand from a hydraulic separator (not shown) is pumped as a liquid slurry to form the piles 30, 31 and 32. The sand-water slurry only contains the minimum amount of water required to transport the pumped sand. Depending on the particular sand, this water content may be as little as 20 percent by weight. This pumped sand is moulded in the piles 30, 31 and 32 to dry to a desired water content between 3 and 10 percent by Weight. The piles 30, 31 and 32 are formed over the delivery tunnel 33 which has an opening 34, 35 or 36 under each sand pile. A vibration activated chute 37, 38 or 39 is disposed, respectively, under each opening 34, 35 and 36. Thus, when a given chute is activated, sand will flow down the chute to be deposited on a conveyor belt 40. As shown, chute 38 is activated to drop sand from pile 31 on conveyor 40. An inclined conveyor belt 41 carries this sand to a storage hopper 42.

As shown in FIGURE 3, a factory building 44 has a raised central portion 45 on which is mounted hopper 42. As has been described, hopper 42 is loaded with sand dried to a desired water content by conveyor belt 41 which is driven by the motor 43. Additional hoppers 46, 47 and 48 are also supported above portion 45 of building 44. By means of air slide chutes 49, 50 and 51 a truck 52 may charge the storage hoppers 46, 47 and 48 with lime or silica flour as required. The lime hoppers 47 and 48 are relatively large as the lime has a relatively great bulk for a given weight. The sand storage hopper 42 need not be very large as a supply of sand is always available from conveyor 41. The storage hoppers 42, 46, 47 and 48 are placed as high as possible on building 44 so that the apparatus which will now be described may be placed below them.

As shown in FIGURE 4, the storage hopper 42 is disposed over the weighing hopper 55 and has an electrically operated sand delivery device 56 at its lower end. The storage hoppers 46, 47 and 48 have screw conveyors 57, 58 and 59 fixed below them to discharge lime and silica flour into weighing hopper 55. Weighing hopper 55 is supported by the strain responsive members 60 which are used to cumulatively weigh a charge 61 and control, by means of pre-set control means (not shown), the device 56 and the conveyors 57, 58 and 59 to deposit a desired charge into the weighing hopper 55. An example of such a charge was 710 pounds of sand with a 4 percent moisture content, 85 pounds of silica flour, 75 pounds of lime, and 12 pounds of water. The Water was added in the mixers 66 and 67 which operated about 30 seconds on a dry charge before the 12 pounds of water were added. Each charge should be about 1000 pounds and be measured with an accuracy of .1 percent to keep actual variations of the ingredients less than .5 percent.

An electrically operated discharge gate 61 dumps the charge in hopper 55 into the travelling hopper 62 which is roller mounted on rails 63 to be moved along the rails 63 by motor 64 and an endless chain 65 or any equivalent mechanism. By means of hopper 62 the measured charge can be deposited in either of the mixers 66 and 67. Each mixer 66 and 67 contains crusher rollers 68 which roll about a rotating vertical axle 69. Scrapers 70 and 71 and the rollers 68 ensure the thorough mixing of each charge which drops when mixed into the lower hopper 72 of each mixer. From each hopper 72, the mixed charge passes through a forming press 73 or 74.

Referring now to FIGURE 5, each forming press 73 4 and 74 has a press bed 75 containing a plurality of brick forming cavities 76. A hopper 72 is disposed behind and above bed 75. The bottom of hopper 72 is open and disposed a slight distance above a belt 77 driven by a motor 78. Motor 78 drives conveyor belt 77 to fill the open bottom bin 79 to a level determined by a level sensing device 80 which stops motor 78 when bin 79 is so filled. A charging box 80 is slidably mounted on an extension 81 of press bed 75 and contains apertures 82. A hydraulic cylinder 83 or other equivalent device moves the charging box 80 forward from the position shown over press bed 75 so that bin 79 fills the apertures 82 passing thereunder with the mixed charge. The then measured charge in the apertures 82 falls in the cavities of the press bed 75 and the charging box 80 is withdrawn.

Upper and lower cylinders 85 and 86 force the platen mounted upper and lower forming dies 87 and 88 into the cavities 76 to compact the mixture therein and form it into bricks or other structural shapes. Each press 73 and 74 is capable of exerting a force of 250 tons which is exerted over a die area of about 360 square inches. Thus, the bricks are formed with a pressure of at least 1500 pounds per square inch. The entire press cycle to form bricks takes about twelve seconds. For at least two seconds and preferably three seconds of this cycle While the forming pressure is being exerted, at least one five pound air hammer 89 delivers over 20 strokes per second to one of the sets of dies 87 or 88. Rotation of the four-way valve 91 alternately delivers compressed air from tube 92 to the ends of cylinder to drive air hammer 89. This pounding of the press dies by an air hammer more uniforrnly compacts to a greater density the bricks formed therein.

Upper cylinder 85 withdraws dies 87 and lower cylinder 86 further extends dies 88 to push formed bricks 93 above the level of the press bed 75. The next forward movement of the charger box 80 pushes the formed bricks 93 into a front extension 94 of the press bed 75. Cylinder 86 withdraws the dies 88 to the position shown to receive another charge.

The rows of bricks 93 are slightly separated from each other by a roller 95 set in extension 94 or by any other suitable mechanism. Transverse tracks 96 have a. vertical cylinder 97 fixed in the roller mounted carriage 97'. Cylinder 97 moves the attached brick holding fingers 98, .99 and 100 downward about the rows of formed bricks 93. Retraction of cylinders 101 and 102 moves the flexible fingers 98 and 100 inward to grasp rows of the formed bricks 93. Cylinder 97 retracts to raise the gripped bricks 93 and carriage 97 is then moved laterally along the tracks 96 to stack the bricks 93 in a manner which will be described.

Referring now to FIGURE 7, rail cars 104 roll on tracks 105 passing alongside each forming press 73 and 74. A motor 106 slides carriage 97 and cylinder 97 along rails 96 to move gripped bricks 93 over a rail car 104. Cylinder 97 extends rod 107 to stack brick 93 on a rail car 104 as shown in FIGURE 8. After brick are stacked to a desired height on one end of a rail car 104 as shown, a cylinder 108 between or parallel to rails 105 extends and retracts its piston rod 109 to move a slide 110. A rail car engaging hook 111 engages a car 104 to move it a desired distance along rails 105. Couplings 112 join a string of rail cars 104 so cylinder 108 can move a large number of cars 104 past a press 73 or 74 to have bricks 93 stacked on them.

Referring further to FIGURE 7, tubular autoclave units 114 are disposed behind the presses 73 and 74 and have pressure tight closures or doors 115 hinged on them. Tracks 116 extend into each autoclave unit 114 with a removable section (not shown) to allow the doors 115 to close. A transverse carrier 118 is electrically driven to roll on track 119 and carries a track section 120 on it. Thus, cars 104 can be loaded with formed brick and rolled into any autoclave unit 114. Turntables 121 enable 5. rail cars 104 to be moved from one side of the brick plant to the other on cross track 122. Tracks 123 extend to one or more loading stations as will be described.

FIGURES 9 and 10 show the manner in which standard size bricks 93 may be stacked on rail cars 104. The bricks are stacked in rows 150 and columns 155 across and along each rail car 104. As shown, standard brick 93 are stacked in six rows of eighteen columns with each brick stacked exactly above the other to a height of fourteen bricks to clear the tubular autoclave 114. A central stack of twelve columns 151 of brick 93 are also in six rows 155 four bricks high may be made on the main stack to increase capacity of the cars 104 while still clearing the autoclave 114. It is to be noted that there are vertical clearances 125 and 126 of at least one quarter of an inch left between the rows and columns of brick 93. These aligned clearances 125 and 126 promote the flow of steam to the faces of the brick which show in construction. As shown in FIGURE 1, these faces are designated by the reference numerals 127 and 128. If adjacent faces 127 or 128 of stacked bricks touch or contact each other in the autoclave 114, they may cure a different color. The bricks are autoclaved at a pressure of over 225 pounds per square inch at a temperature of over 390 F., for at least seven hours. A successful test production sample autoclaved brick at 250 pounds per square inch at 407 F. for eight hours. In a steam environment, the humidity in the autoclaves is always 100 percent.

The autoclaved bricks 93 on the rail cars 104 are moved from the autoclave units 114 to an unloading station as shown in FIGURES 11 and 12. The station has three unloading positions 130, 131 and 132 disposed alongside rails 123. Each unloading position has a roller conveyor 133 supported on a frame 134 to have one end cantilevered towards rails 123. A side wall 135 is fixed along the end of each roller conveyor 133. A retaining door 136 is hinged to and normally closed at right angles to wall 135 but door 136 may be opened to be swung away from rails 123. The roller conveyors 133 are supported at a slight incline so brick stacked thereon may roll away from rails 123 when the doors 136 are opened. Each conveyor 133 has a platform 137 on which a worker may stand. The conveyors of the unloading positions 130, 131 and 132 are progressively positioned to extend further over the rail cars 104. Thus, as shown, a worker at position 130 unloads the right third of the cars 104 as shown in FIGURE 11, a worker at position 131 unloads the center third of the cars 104, and a worker at position 132 unloads the left third of the cars 104.

The stacking configuration of brick n the rail cars 104, as shown in FIGURES 9 and 10, allows each worker to unload substantially one third of a car as each worker may cut down or only remove those rows 150 or 151 on his third of a car 104. Thus, each worker need only handle and move brick a minimum distance as cars 104 are advanced through the unloading station.

The workers in the unloading station stack brick on the conveyors 133 against a wall 135 and a closed door 136 in a stack 140 as shown in FIGURE 13. The stack 140 is secured by the steel bands 141. Thin wooden slats (not shown) span the second layer 143 of the brick 93. This permits two rows of two brick each to be left out in this second layer 143 to accommodate the blades of a fork lift truck. The thin wooden slats allow the bricks in the third layer 144 to bridge the missing bricks. When a stack 14 is completed and banded on a conveyor 133, a door 136 is opened allowing the stack 140 to roll along the conveyor.

The process and apparatus herein described particular ly lends itself to almost complete automatic operation and resulting better control. Well known circuits of interlock switches make a given operation await completion of a prior or a following operation. For example, sand from a pile 30, 31 or 32 may be removed automatically by tunnel 33 and conveyor 41 when the sand in storage hopper 42 falls below a given level. The storage hoppers of FIGURE 4 only meter out a desired mixture or charge into weighting hopper 55 when one of the mixer hoppers 72 is almost empty. Travelling hopper 62 then charges the almost empty mixer 66 or 67. The

. cycle within the presses 73 and 74 has been explained.

Thus, it may be seen that the passage of materials through the forming presses 73 and 74 may automatically deter mine the feed of these materials as an accurately mixed charge to these presses.

The bricks 93 are continually stacked as they are formed on the cars 104 by the devices which have been described. These devices are programmed by well known cam devices to produce the desired stacking pattern. After a given number of cars are loaded, they are moved into an autoclave unit 114. The autoclaved brick 93 are then packaged in a loading station as has been described.

As shown in FIGURES 1 and 6, brick 93 may have bottom cavities 149 formed therein by retracting plungers (not shown) in the dies 88. Roman brick and other building blocks may be made by the process of this invention.

While this invention has been shown and described in the best form known, it will nevertheless be understood that this is purely exemplary and that modifications may be made without departing from the spirit and scope of the invention.

What is claimed is:

1. The process of making brick comprising the steps of:

(a) feeding graded sand with a moisture content of between 3 and 10 percent and with less than 2 percent mud and salt impurities to an elevated storage hopper;

(b) filling additional elevated storage hoppers with lime and with silica;

(c) consecutively passing graded sand and lime and silica into a weighing hopper below the storage hoppers while cumulatively weighing charges of sand and lime and silica;

(d) passing the weighed charges into a mixer mixing the charges with water to provide a mixed charge;

(eLpassing the mixed charge into an open bottom (f) moving a charging box below the bin and over apertures in a forming press bed to charge the formmg press;

(g) exerting a forming pressure in the press of at least 1,500 pounds per square inch while pounding a platen of the press with an air hammer for at least two seconds;

(h) removing formed brick from the press;

(i) stacking the formed brick on rail cars, one brick directly over the other in rows and columns with at least one quarter inch clearance between rows and columns;

(j) autoclaving the stacked brick on the rail cars with steam for at least seven hours at a temperature of over 390 F., at a pressure of over 225 pounds per square inch; and

(k) passing the stacked brick on the rail cars through an unloading station with staggered progressively arranged unloading positions to unload a longitudinal portion of the rail cars at each unloading position.

References Cited UNITED STATES PATENTS 663,904 12/1900 Kleber 264-333 809,053 1/1906 Gordon 25-133 1,327,721 1/1920 Mattison 264-333 X 1,462,596 7/1923 Engelbrecht 264333 X 2,696,353 12/1954 Vessels 25-103 (Other references on following page) UNITED STATES PATENTS FOREIGN PATENTS OTHER REFERENCES Eirich 25103 X Harrop Car Tunnel Kiln, publication found in 25, Kiln Hoopes 106120 X Car Digest.

Howard 25-2 X Concrete Information, Structural Bureau, Portland Gard 25-103 X 5 Cement Association, December 1948, Bulking of Sand Kalousek 106-120 Due to Moisture.

Sekiguchi 264-71 X Britner 25-1 03 ROBERT F. WHITE, Primary Examiner Kupka 1816.5 X

Blecko X 10 N.RUSHEFSKY,Ass1stant Examiner US. Cl. X.R.

Great Britain.

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3904723 *Nov 16, 1972Sep 9, 1975Castone Development CorpConcrete product manufacturing system and method
US4036575 *Jun 9, 1975Jul 19, 1977Castone Development CorporationConcrete product manufacturing system
US4063859 *Jul 1, 1976Dec 20, 1977Gary L. HalleApparatus for producing shaped concrete products
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Classifications
U.S. Classification264/71, 425/130, 425/88, 264/234, 425/148, 425/213, 425/200, 425/256, 264/238, 425/404
International ClassificationB28B17/02, B28B3/02, B28B13/00, B28B13/02, B28B17/00, B28B15/00
Cooperative ClassificationB28B13/023, B28B17/02, B28B3/02, B28B15/007, B28B15/00
European ClassificationB28B15/00C, B28B15/00, B28B17/02, B28B13/02D4, B28B3/02